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The above is an example of when the duplicate system breaks. The
Possible Duplicate banner is still present, but most users won't be able to see the linked question. One comment even recommended a scraper that allowed them to view the question in (er...) question.
My question is what should happen to questions like these? Should the duplicate be unmarked? That may not be the best because in this case, both questions are off-topic and deserve deletion. What else could be done?